Mechanical
Counterbalance Spring
Offsets the static weight of the arm at the J2 joint to reduce continuous torque demand on the motor and brake.
The counterbalance spring pushes against the lower arm to partially offset the weight of the arm structure above the J2 joint, reducing the continuous torque the J2 servo motor and brake need to hold and move the arm.
Because the spring is under constant high preload, it is engineered with a generous fatigue life, but a cracked or fully failed spring shifts that load back onto the motor and brake, shortening their service life as a secondary effect.
Spring-type counterbalances are common on mid-size robots, while heavier robots more often use a gas or hydraulic counterbalance cylinder for the same purpose.
Related components
Common questions
- What does the Counterbalance Spring do?
- Offsets the static weight of the arm at the J2 joint to reduce continuous torque demand on the motor and brake.
- How does the Counterbalance Spring fail?
- Common failure modes: Fatigue cracking after extended service life, Complete spring failure shifting load onto the J2 motor and brake, Mounting bracket wear or loosening, Corrosion reducing spring fatigue life in harsh environments.
- What fault codes relate to the Counterbalance Spring?
- Related codes include SRVO-021, SRVO-068.